Recreational use of water facilities such as lakes, reservoirs, and the oceans, has increased in recent years. This increase in use arises from a number of factors including relatively inexpensive power and sail boats, additional leisure time, and easier, more rapid access to boating facilities. Recreational boating activities include cruising, swimming, fishing and water skiing. These activities involve a number of persons, and some water facilities have become crowded.
Crowded water facilities pose risks to persons using the facilities, and especially to water skiers. A skier bobbing in the open water typically is either preparing to ski or after falling, is waiting for the ski boat to return. The skier in the water is especially at risk from other boaters. The skier is low in the water; the other boaters are above the water. Glare, speed, and inattention may prevent the boater from seeing the skier. It is important therefore for an operator of a boat pulling a skier to learn quickly that the skier has fallen. The operator may then circle back to pick up the skier. The boat also provides a larger structure that may be seen at a distance to alert other boaters of the presence of a skier in the water.
Signaling devices have been developed to alert the operator of the ski boat that the skier has fallen into the water. For example, U.S. Pat. No. 4,483,683 issued to Alley, Sr. describes a ski tow rope which fastens in a conventional manner to the ski boat. The distal end of the rope carries a handle provided with a radio signal transmitter and a trigger wholly contained within the handle. Depressing the trigger stops the transmitter from sending a signal to a receiver in the boat. Releasing the trigger, such as when the skier falls into the water, activates the transmitter to send the signal. Upon receipt of the signal, the receiver alerts the operator by a noise or light alarm. For example, a strobe light mounted high in the boat on the windshield alerts both the operator and other operators of nearby boats.
U.S. Pat. No. 4,689,611 issued to Franklin describes an alarm and communication system for water skiers pulled by power boats. A radio receiver receives a constantly emitted signal from a transmitter housed in a handle at the ski rope or attached to a life vest worn by the skier. An alarm switch in the receiver provides a closed contact in the absence of the receipt by the receiver of a signal, such as when the skier releases the handle. Submergence of the antenna and the increasing distance between the boat and the skier results in a diminished signal, such that the alarm switch then closes to activate an alarm. Such device however, has drawbacks which may trigger false alarms. The transmitter is always operating during use, which depletes the power supply. Weak or low batteries may diminish the power of the transmitted signal. A diminished signal may result in the alarm being triggered in the boat, yet the skier would be properly skiing. Also, while the skier is preparing to ski, the antenna is covered by water. This too diminishes the strength of the radio signal and may activate the alarm. To avoid inadvertent activation, the receiver must first be switched off, and thereafter activated so the alarm system can operate. Such on/off switching may prove to be annoying or perchance forgotten, so that the skier is skiing with a false sense of security relying on an alarm that is not activated.
While accomplishing the intended purpose, such signal devices have drawbacks which discourage their use. The electronics for the receiver and transmitter are costly. The transmitter is build-in to the handle of the ski tow rope. Should the rope or the handle break, the signal device cannot be used. Repair of the device may require returning the transmitter and rope to the manufacturer. The attempt to overcome this problem by positioning the alarm transmitter on the skier leads to possible false alarms or unintentional non-use of the alarm device, as discussed above.
Accordingly, there is a need in the art for a radio signal transmitter that is releasably attachable to the handle of a ski tow rope, thereby permitting repair of a broken rope or handle while keeping the transmitter in close proximity to the receiver.